Lineage for d2or4a2 (2or4 A:118-350)

Fold c.8: The "swivelling" beta/beta/alpha domain [52008] (10 superfamilies)3 layers: b/b/a; the central sheet is parallel, and the other one is antiparallel; there are some variations in topology
this domain is thought to be mobile in most multi-domain proteins known to contain it